process: runtime deprecate coercion to integer in process.exit()

This is a follow up of doc-only deprecation
#43738.

Signed-off-by: Daeyeon Jeong daeyeon.dev@gmail.com
PR-URL: #44711
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: daeyeon

doc/api/deprecations.md

@@ -3175,6 +3175,9 @@ thing instead.
 
 <!-- YAML
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/44711
+    description: Runtime deprecation.
   - version: v18.10.0
     pr-url: https://github.com/nodejs/node/pull/44714
     description: Documentation-only deprecation of `process.exitCode` integer
@@ -3187,7 +3190,7 @@ changes:
                  coercion.
 -->
 
-Type: Documentation-only
+Type: Runtime
 
 Values other than `undefined`, `null`, integer numbers, and integer strings
 (e.g., `'1'`) are deprecated as value for the `code` parameter in

lib/internal/bootstrap/node.js

@@ -102,6 +102,31 @@ process.domain = null;
 }
 process._exiting = false;
 
+{
+  const warnIntegerCoercionDeprecation = deprecate(
+    () => {},
+    'Implicit coercion to integer for exit code is deprecated.',
+    'DEP0164'
+  );
+
+  let exitCode;
+
+  ObjectDefineProperty(process, 'exitCode', {
+    __proto__: null,
+    get() {
+      return exitCode;
+    },
+    set(code) {
+      if (perThreadSetup.isDeprecatedExitCode(code)) {
+        warnIntegerCoercionDeprecation();
+      }
+      exitCode = code;
+    },
+    enumerable: true,
+    configurable: false,
+  });
+}
+
 // process.config is serialized config.gypi
 const nativeModule = internalBinding('builtins');
 

lib/internal/process/per_thread.js

@@ -13,7 +13,10 @@ const {
   ArrayPrototypeSplice,
   BigUint64Array,
   Float64Array,
+  Number,
+  NumberIsInteger,
   NumberMAX_SAFE_INTEGER,
+  NumberMIN_SAFE_INTEGER,
   ObjectFreeze,
   ObjectDefineProperty,
   ReflectApply,
@@ -180,9 +183,23 @@ function wrapProcessMethods(binding) {
 
   memoryUsage.rss = rss;
 
+  const { deprecate } = require('internal/util');
+  const warnIntegerCoercionDeprecationSync = deprecate(
+    () => {},
+    'Implicit coercion to integer for exit code is deprecated.',
+    'DEP0164',
+    true
+  );
+
   function exit(code) {
     process.off('exit', handleProcessExit);
 
+    if (isDeprecatedExitCode(code)) {
+      // Emit the deprecation warning synchronously since deprecation warning is
+      // generally emitted in a next tick but we have no next tick timing here.
+      warnIntegerCoercionDeprecationSync();
+    }
+
     if (code || code === 0)
       process.exitCode = code;
 
@@ -407,6 +424,23 @@ function toggleTraceCategoryState(asyncHooksEnabled) {
   }
 }
 
+function isDeprecatedExitCode(code) {
+  if (code !== null && code !== undefined) {
+    const value =
+      typeof code === 'string' && code !== '' ? Number(code) : code;
+    // Check if the value is an integer.
+    if (
+      typeof value !== 'number' ||
+      !NumberIsInteger(value) ||
+      value < NumberMIN_SAFE_INTEGER ||
+      value > NumberMAX_SAFE_INTEGER
+    ) {
+      return true;
+    }
+  }
+  return false;
+}
+
 module.exports = {
   toggleTraceCategoryState,
   assert,
@@ -415,4 +449,5 @@ module.exports = {
   hrtime,
   hrtimeBigInt,
   refreshHrtimeBuffer,
+  isDeprecatedExitCode,
 };